高中英语Unit 15 Lesson 1教学指导 北师大版 必修5

高中英语Unit 15 Lesson 1教学指导北师大版必修5
1.What is it about the world today that makes it necessary to continue learning?
该句是一个强调句式。

强调句式的用法：
强调结构的形式是：“It + be的适当形式+ 被强调部分+ that/who +剩余部分”，它常用来突出说话人要强调的语言信息，给对方以强烈的印象和感受。

在本结构中，it无意义，不能换成this 或that；若原句时态是现在时或将来时，be 则用is；若原句谓语动词是过去式，则be 用was；有时也可根据需要在be前面加上may，might，must等情态动词；若被强调部分是人，引导词用who或that 均可以，若强调部分其他部分，一律用that。

译成汉语时常加上“正是。

”等字眼。

Eg: It was in Greece that Olympic Competitions firstly started.
奥林匹克运动会就是在希腊首次开始举行的。

It must be John that/who will take part in the contest on behalf of our class.
肯定是约翰将代表我们班参赛。

应用强调结构，应注意以下几点：
（1）被强调代词的格应与原句保持一致，其谓语动词与原句主语保持一致
eg: It is I who am going to Beijing next week.
It is him who I want to see.
（2）强调结构也有其否定，问句或感叹形式。

特殊问句中只有疑问词可以被强调，构成：“特殊疑问词+ be + it + that +剩余部分”结构。

Eg: Was it during the Second World War that he died?
他是在第二次世界大战期间死亡的吗？
Where was it that you met Tom yesterday?
昨天你是在哪儿碰到汤姆的？
What a wonderful time it was that we had at the party!
我们在聚会上玩得多么高兴啊！
（3）强调结构的反意问句，附加问句中的主语用it 而不用句中主语。

Eg: It was at eleven last nigh t that I knew the good news, wasn’t it?
是昨天晚上十一点我知道这个好消息的，不是吗？
It is where you come from that you should return to, isn’t it?
你是从哪里来的就应回到哪里去，不是吗？
（4）对not。

until/till结构中的状语进行强调时，not 需要置于被强调部分之中，构成“It is/was not until。

that。

”结构。

Eg: It was not until she took off her dark glasses that I recognized she was a famous film star.
直到她拿下墨镜，我才认出她是位著名影星。

It was not until he finished all his homework that he went to bed last night.
昨天晚上直到他完成作业才睡觉。

（5）本强调结构不能用来强调让步状语从句，原因状语从句中只有because引导的可被强调。

是因为他病得厉害，昨天才没有上学。

Eg:It was because he was seriously ill that he didn’t go to school yesterday.
2.grammar:third conditional
(1)与现在事实相反的虚拟条件句
在条件状语从句中,如果假设的条件不能符合现在的实际情况,主从句必须使用虚拟语气.其结构为:
If sb.did(were)…, sb.would(should,could,might)+动词原形.
注意:
从句中的动词were可用于各种人称,主句中的should只可用于第一人称单数. Eg: If I were you,I would not do it.
如果我是你,我不会做这件事的.
If he had time, he would go to the concert with you.
如果他有时间,他会和你一起去参加音乐会的.
If it were not for the expense,I would go to Italy.
如果不是因为费用问题,我会去意大利的.
(2) 与过去事实相反的虚拟条件句
在条件状语从句中,如果假设的条件不能符合过去的实际情况,主从句必须用虚拟语气. 其结构为:
If sb.had done sth…, sb.would(should,could,might)+动词完成式(have done sth.).
注意:
在这一结构中,如果从句中有过去时间状语,其谓语动词也不能用一般过去式.
Eg :If my lawyer had been here last Saturday, he would have prevented me from going there.
如果上周六我的律师在这里,他会阻止我去那里的.
If it hadn’t been for your help,I couldn’t have finished it ahead of time.
要不是你的帮助,我不会提前完成任务的.
(3) 与将来事实相反的虚拟条件句:
在条件状语从句中,如果假设的条件不能符合将来的实际情况,主从句必须用虚拟语气.其结构为:
If sb.did(were to/should do) sth…, sb.would(should,could,might)+动词原形.
注意:
从句中的should或were可用于各种人称,从句中无论哪种人称都不可用would. Eg: If I should see him this afternoon,I would give the note to him.
如果今天上午我能看到他的话,我会把便条给他的.。